How to add doctype in TYPO3
Sets the document type for the XHTML version of the generated page.
If config.doctype is set to a string then config.xhtmlDoctype must be set to one of these keywords:
xhtml_trans for XHTML 1.0 Transitional doctype.
xhtml_frames for XHTML 1.0 Frameset doctype.
xhtml_strict for XHTML 1.0 Strict doctype.
xhtml_basic for XHTML basic doctype.
xhtml_11 for XHTML 1.1 doctype.
xhtml_2 for XHTML 2 doctype.
This is an example to use MathML 2.0 in an XHTML 1.1 document:
config.doctype ( <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1 plus MathML 2.0//EN" "http://www.w3.org/Math/DTD/mathml2/xhtml-math11-f.dtd"> ) config.xhtmlDoctype = xhtml_11
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